Radiofrequency (RF) communications, such as for mobile telephony and cable television, may use an RF power amplifier (PA) circuit in an RF transmitter to produce the RF signal for transmission over the air to an RF receiver. The PA circuit may have a nonlinear gain characteristic, such as gain compression occurring at higher power output levels, which can lead to signal distortion at such higher power levels. Digital predistortion (DPD) is used to pre-distort input to a PA to reduce distortion in the output of the PA.